Gluster Expands Open-Source Scale-out NAS

Tuesday Feb 8th 2011 by Drew Robb

The company claims the first scale-out virtual NAS appliances for VMware and Amazon Web Services (AWS).

Open-source storage vendor Gluster has introduced a couple of new additions to its scale-out NAS platform. The company claims these are the first scale-out virtual NAS appliances for VMware and Amazon Web Services (AWS). Known as the Gluster Virtual Storage Appliances, they come in two flavors  one for virtual machines (VMs) and one for Amazon-based clouds.

The VMware Virtual Storage Appliance integrates the Gluster File System (GlusterFS) into a virtual machine for deployment on any VMware-certified hardware or cloud platform, and can be deployed in minutes. For Amazon Web Services, GlusterFS is packaged in an Amazon Machine Image (AMI) for deployment on the AWS public cloud.

This is the next step in virtualization  deploying storage resources in a similar way to compute resources, said Jack OBrien, vice president of marketing at Gluster. The software enables the pooling of back-end disk.

He explained that many organizations are struggling to virtualize storage. The reason, he said, is that most virtualized storage is SAN-based and typically adopts a scale-up approach: You buy larger and larger hardware units as your storage needs expand. However, this presents some problems with VMware performance.

You get I/O bottlenecks when lots of VMs are banging on the same piece of data, said OBrien. You also are faced with LUN limitations and complexity, lots of manual management, and the expense of Fibre Channel.

Gluster provides a scalable NAS alternative with a single mount point. The software does all the data distribution and I/O load balancing and can be loaded on commodity hardware. OBrien said that anyone running VMware, for example, can deploy Gluster on top of the VMware ESX layer or by going to the Amazon marketplace and starting up an Amazon web service.

OBrien added that Gluster overcomes some significant limitations on the Amazon EC2 platform. For example, it has a 2TB limitation for its Elastic Block Storage (EBS). Further, an EC2 instance can only talk to one EBS volume at a time.

Gluster aggregates multiple EBS storage with no size limits, said OBrien. It is the only way to built multi-client access to shared storage on Amazon.

Gluster offers these products on a subscription basis. Those already on a subscription dont need to pay extra for these new services. The fee per storage server per year starts at $4,000, and there are two tiers of subscription available.

How do Gluster Virtual Storage Appliances compare to what is out there in the market? OBrien said that Isilon (acquired by EMC) is probably the closest, although Isilon takes an integrated hardware and software approach as opposed to Glusters software-only strategy.

The primary use cases for this scale-out architecture are either on-premise NAS storage where a company has hit the wall on existing NAS performance, as shared storage for VMware, and for service providers offering public cloud services.

Gluster, though, does not tackle databases or other structured data platforms  only unstructured data. Users can begin with 50TB to 100TB and then add more capacity on demand.

Analyst Take

Terri McClure, an analyst with the Enterprise Strategy Group (ESG), believes that interest in scale-out storage has significantly increased recently as enterprises look for the most effective way to address scalability and manageability in dynamic environments such as cloud computing and virtual environments.

Glusters new offering is representative of the types of major breakthroughs were seeing in storage technology for VM and cloud environments, delivering the scale-out architecture that is needed in a highly responsive manner thanks to its software approach to the problem, said McClure.

Greg Schulz, an analyst with the Server and StorageIO Group, thinks Gluster has a good solution for companies looking to leverage scale-out NAS for traditional, virtual, private or public cloud environments.

Their approach of providing flexibility to deploy the technology on different platforms to meet various business or application needs is an example of what scale-out should be about  scale functionality, ease of use, flexible to adapt to different needs while supporting performance, availability, capacity and security with multi-tenancy for virtual, physical and cloud environments, said Schulz. This removes some complexity from cloud and virtual environments by reducing the need for a cloud access gateway, appliance or software driver, which should help to reduce costs -- including management.

Drew Robb is a freelance writer specializing in technology and engineering. Currently living in California, he is originally from Scotland, where he received a degree in geology and geography from the University of Strathclyde. He is the author of Server Disk Management in a Windows Environment (CRC Press).